Allow a self-hosted user to configure their SMTP settings directly from within the UI (#682)

* Add setting fields to model

* Allow to configure SMTP settings

* Normalize locales

* Cleanup locales

* Remove 'coming soon'

* fix test

* Reset credentials

* Reset development config

* Check smtp spelling

* Use post instead of get method

* TLS ENV variable is more descriptive

* Rework application mailer

* Follow rails convention for mailer action params

* Reset schema.rb to main

* Test WIP

* Add test for controller and mailer

* Move tests from controller to model

* Custom error message if settings are not all present

* Comment smtp config in development env

* Add default tls enabled value

* Rubocop

* Fix controller test

* Reset credentials

* Normalize locales

* Test

* fix test

* Fix application mailer test that fails randomly

* Error flash message instead of notice

* Rework application mailer tests

test/controllers/settings/hostings_controller_test.rb

@@ -44,4 +44,38 @@ class Settings::HostingsControllerTest < ActionDispatch::IntegrationTest
     assert_equal "release", Setting.upgrades_target
     assert_equal NEW_RENDER_DEPLOY_HOOK, Setting.render_deploy_hook
   end
+
+  test " #send_test_email if smtp settings are populated try to send an email and redirect with notice" do
+    Setting.stubs(:smtp_settings_populated?).returns(true)
+
+    test_email_mock = mock
+    test_email_mock.expects(:deliver_now)
+
+    mailer_mock = mock
+    mailer_mock.expects(:test_email).returns(test_email_mock)
+
+    NotificationMailer.expects(:with).with(user: users(:family_admin)).returns(mailer_mock)
+
+    post send_test_email_settings_hosting_path
+    assert_response :found
+    assert controller.flash[:notice].present?
+  end
+
+  test "#send_test_email with one blank smtp setting" do
+    Setting.stubs(:smtp_settings_populated?).returns(false)
+    NotificationMailer.expects(:with).never
+
+    post send_test_email_settings_hosting_path
+    assert_response :unprocessable_entity
+    assert controller.flash[:error].present?
+  end
+
+  test "#send_test_email when sending the email raise an error" do
+    Setting.stubs(:smtp_settings_populated?).returns(true)
+    NotificationMailer.stubs(:with).raises(StandardError)
+
+    post send_test_email_settings_hosting_path
+    assert_response :unprocessable_entity
+    assert controller.flash[:error].present?
+  end
 end

test/mailers/application_mailer_test.rb

@@ -0,0 +1,45 @@
+require "test_helper"
+
+class ApplicationMailerTest < ActionMailer::TestCase
+  setup do
+    class TestMailer < ApplicationMailer
+      def test_email
+        mail(to: "testto@email.com", from: "testfrom@email.com", subject: "Test email subject", body: "Test email body")
+      end
+    end
+  end
+
+  test "should use self host settings when self host enabled" do
+    ENV["SELF_HOSTING_ENABLED"] = "true"
+
+    smtp_host = "smtp.example.com"
+    smtp_port = 466
+    smtp_username = "user@example.com"
+    smtp_password = "password"
+    email_sender = "notification@example.com"
+
+    smtp_settings_from_settings = { address: smtp_host,
+                                    port: smtp_port,
+                                    user_name: smtp_username,
+                                    password: smtp_password }
+
+    Setting.stubs(:smtp_host).returns(smtp_host)
+    Setting.stubs(:smtp_port).returns(smtp_port)
+    Setting.stubs(:smtp_username).returns(smtp_username)
+    Setting.stubs(:smtp_password).returns(smtp_password)
+    Setting.stubs(:email_sender).returns(email_sender)
+
+    TestMailer.test_email.deliver_now
+    assert_emails 1
+    assert_equal smtp_settings_from_settings, ActionMailer::Base.deliveries.first.delivery_method.settings.slice(:address, :port, :user_name, :password)
+  end
+
+  test "should use regular env settings when self host disabled" do
+    ENV["SELF_HOSTING_ENABLED"] = "false"
+
+    TestMailer.test_email.deliver_now
+
+    assert_emails 1
+    assert_nil ActionMailer::Base.deliveries.first.delivery_method.settings[:address]
+  end
+end

test/models/setting_test.rb

@@ -0,0 +1,23 @@
+require "test_helper"
+
+class AccountTest < ActiveSupport::TestCase
+  test "#send_test_email return true if all smtp settings are populated" do
+    Setting.smtp_host = "smtp.example.com"
+    Setting.smtp_port = 466
+    Setting.smtp_username = "user@example.com"
+    Setting.smtp_password = "notification@example.com"
+    Setting.email_sender = "password"
+
+    assert Setting.smtp_settings_populated?
+  end
+
+  test "#send_test_email return false if one smtp settings is not populated" do
+    Setting.smtp_host = ""
+    Setting.smtp_port = 466
+    Setting.smtp_username = "user@example.com"
+    Setting.smtp_password = "notification@example.com"
+    Setting.email_sender = "password"
+
+    assert_not Setting.smtp_settings_populated?
+  end
+end